The invention relates to bicycles and comprises a top tube member, saddle and two steerable wheels mounted in a longitudinal direction, each having its own steering control. More specifically, the present invention relates to bicycles which can be used to traverse smooth and rough terrain including mountain slopes.
A regular bicycle has a single steering control (handlebar) that steers the front wheel. The riders hands grip either ends of the handlebar and operates the steering control by pushing with one hand and pulling with the other hand; or visa versa. Thus both hands are involved with operating this single steering control.
For about 18 months I have been riding bicycles based on this inventors U.S. Pat. No. 6,598,892 entitled “Two wheel steering bicycle with latitudinal aligned wheels”. The rider is positioned perpendicular to the direction of motion and the two steerable wheels are controlled by the rider's left and right hand respectively. These steering controls are independent and they are not linked in any way.
I notice that the operation of front and rear steering are rarely symmetric and the operation of the rear steering is generally delayed by up to 2 seconds. The front and rear steering inputs are generally 50:50 in normal operation. The orientation of the inner ear canals that detect human balance are not aligned along the vertical and horizontal axed. This has left me confused as to the operation of this bicycle (U.S. Pat. No. 6,598,892).
I made the observation that the human is quite capable of steering independently and out of phase in this manner. I believe that this human capacity is derived from the general left to right symmetry of the human body. Also when thinking about the human walking motion I notice that the operation of the left leg is largely the same as operation of the right leg but 90 degrees out of phase.
Rethinking why this bicycle (U.S. Pat. No. 6,598,892) works so well, I now believe it is a combination of two steering controls and the correct leverage. I still believe that the human balance capacity in the front to back direction is a great instrument. This leads to the current invention; a two wheel steering forward facing bicycle with two steering controls.
There are a number of two wheel steering bicycles in the prior art.
These include:
Matsuda U.S. Pat. No. 4,650,021 entitled “Rear wheel steering device for motorcycles having limited means”.
Matsuda et al. U.S. Pat. No. 4,664,214 entitled “Motorcycle having steered front and rear wheels with control for ratio”
Frye U.S. Pat. No. 4,733,742 entitled “Two wheeled steerable vehicle”.
Frye U.S. Pat. No. 4,157,739 entitled “Motorcycle”.
Sato et al. U.S. Pat. No. 4,650,022 entitled “Rear wheel steering device for motorcycles”
Summers U.S. Pat. No. 5,485,893 entitled “Vehicle”.
The Drysdale two wheel drive two wheel steering motorcycle (http://home.mira.net/˜iwd/2x2x2/index.html).
Tony Foale discussion of two wheel steering with linked steering (http://www.tonyfoale.com/Articles/2WD—2WS/2WD—2WS.htm).
Tony Foale picture of two wheel steering bicycle with linked steerings (http://www.tonyfoale.com/gallery/PlayTime/pages/172WS_JPG.htm).
All of the prior art have one steering control that control both front and rear steering.
Other two wheel steering devices with linked steerings include:
Hoeksta U.S. Pat. No. 6,102,420 entitled “Walking cycle with steerable front and rear wheel”
Maebe, U.S. Pat. No. 4,506,902 entitled “Bicycle with steerable wheels” describe a device where the front wheel is steered with a regular two handed handlebar and the rear wheel is steered by the seat and or the pedal crank.
The present invention discloses a two wheel steering bicycle with two steering controls and rider positioned facing forward. This will leverage human left to right balance. The user sits on a saddle connected to the seat tube and balances the device by continuously correcting the orientation of the front and rear wheel with his/her first and second hand respectively. The user's body faces the direction of motion. The saddle, front and back steering handles should be adjusted to position the user's body to roughly balance the left to right center axis of the device.
The user's left hand is held to the left side of the user's body and contacts one of the steering handles. The user's left hand is sufficiently clear of the user's body to allow either pushing or pulling of the steering handle.
The user's right hand is held to the right side of the user's body and contacts the other of the steering handles. The user's right hand is sufficiently clear of the user's body to allow either pushing or pulling of the steering handle. The user's left and right hand operate independently and can execute whatever control to maintain the user in an upright position. The user must be in a state of constant correction which with practice will become natural and reflex. This device moves the user in a forward direction. The invention is configured with a saddle and a means of powering the device. Preferably the means of propelling the device is a regular bicycle bottom bracket, front sprocket, crank and pedals driving a bicycle chain connected to the rear wheel. The device could also be configured with a bicycle chain connected to the front wheel or indeed both rear and front wheels. The device could also be configured with a linear drive system. Propelling the device requires actions similar to a regular bicycle. The user moves the pedals in a circular motion which drives the drive chain and the rear wheel. Once the user has mastered the basics of propulsion and turning the user can start introducing his/her weight into the turns by leaning into the turns. The feedback from this device is strongest when the user uses his/her weight. This will excel at carving turns and will work best on open paved areas or grass slopes. It is expected that this invention will be more expressive than a regular bicycle and will reward the operator with much positive feedback of having mastered his/her balance.